Performers Roni, Liv and Becky behind the scenes at Great Yarmouth Hippodrome Circus, England. (Photo by Nick Warner/The Guardian)

Russian cadets march during the annual cadet schools get-together in Moscow, Russia on March 30, 2018. (Photo by Mladen Antonov/AFP Photo)

A hint of Spring Fever is evidenced by this passerby tipping his hat to a store fixture mannequin on a State St. sidewalk in downtown Chicago on March 23, 1978. The mannequin was awaiting pickup to be transported. (Photo by AP Photo)

A picture made available 26 April 2016 shows a tiger playing in the water with a trainer nicknamed “Super Tiger Man” at the Tiger Temple in Kanchanaburi province, Thailand, 24 April 2016. The site known in Thai as “Wat Pa Luangta Maha Bua Yannasampanno” has been the focus of a dispute with the Department of National Parks, Wildlife and Plant Conservation (DNP) after the DNP asked in 2015 that the temple hands over its 147 tigers since it was not licensed to keep them. The temple has requested for a zoo license according to its managing director. (Photo by Diego Azubel/EPA)

In this September 10, 1977, file photo, from left, Hua Guofeng, Chinese Communist Party (CCP) chairman and Mao Zedong's immediate successor; Ye Jianying, CCP vice chairman and future ceremonial head of state; Deng Xiaoping, no formal titles at the time but soon to emerge as paramount leader during the reform era; Li Xiannian, CCP vice chairman and future president; Wang Dongxing, head of the leadership bodyguard unit who helped topple the Gang of Four, view the body of later Chinese leader Mao Zedong in Beijing. (Photo via AP Photo)

In this February 19, 2017 photo, a couple dances during the “If you don't give me....then you lend me” Carnival street party on Ipanema beach, in Rio de Janeiro, Brazil. The typical view of Carnival in Brazil is anything goes, with no headdress too big, no outfit too small, no song too ribald, but this year some organizers of the world's best known party are drawing the line at lyrics that are sexist, homophobic or racist. (Photo by Silvia Izquierdo/AP Photo)

Russian honor guard soldiers warm up prior a rehearsal for the Victory Day military parade in St. Petersburg, Russia, Wednesday, May 3, 2017. The parade will take place at Dvortsovaya (Palace) Square on May 9, to celebrate 72 years after the victory in WWII. (Photo by Dmitri Lovetsky/AP Photo)

A police officer stands at a police cordon near the scene of a terror attack in London, U.K., on Sunday, June 4, 2017. A van swerved into Saturday-night crowds on London Bridge, before three men got out and went on a stabbing rampage through nearby bars. (Photo by Luke MacGregor/Bloomberg)